Hesitation on initial acceleration

[liberty]

Carburetor: Edelbrock Quadrajet (NOS)   Numbers: 1904, 8907, 0870 W

Problem:  Hesitation, from a stop, during initial acceleration. No other hesitation or problems.  This carb had never been used since manufactured.

A different Quadrajet (Rochester) had been on this engine/car with no hesitation – all sources of vacuum leaks have been checked.

Are there any exterior correcting adjustments?  If not – recommendation/solution?   

[Schurkey]

Carburetor: Edelbrock Quadrajet (NOS)   Numbers: 1904, 8907, 0870 W

Problem:  Hesitation, from a stop, during initial acceleration. No other hesitation or problems.  This carb had never been used since manufactured.

A different Quadrajet (Rochester) had been on this engine/car with no hesitation – all sources of vacuum leaks have been checked.

Are there any exterior correcting adjustments?  If not – recommendation/solution?   

Does the accelerator pump work?

Is the air valve spring-loaded shut?

[liberty]

I've decided to start diagnostic by richening APT.

[omaha]

that would be worth a try. If it is an edelbrock, it still must be fairly old as they were disco'd some years ago. I would get a new accel pump and top gasket.  My guess is the accel pump is not sealing (from sitting too long).....just my first guess.  [cliff's got the good one's!!]  one trick: disconect the accel pump linkage and try driving it, see if it makes a difference. If no difference,[or little difference] accel pump is probably bad. {try this after the car has warmed, it'll be easier to start}